/// <summary>
/// Helper method that helps to draw the ship. Picks the correct sprite for current ship.
/// </summary>
/// <param name="s">a ship object</param>
/// <returns>the corresponding Image sprite</returns>
private Image DrawShip(Ship s)
{
// if coasting, return coasting
if (!s.IsThrusting())
{
// retrieve image from CoastingShips image dictionary
return(CoastingShips[s.GetID() % 8]);
}
// else, return thrusting
else
{
// retrieve image from CoastingShips image dictionary
return(ThrustingShips[s.GetID() % 8]);
}
}
/// <summary>
/// Calculates the instant acceleration from stars and engine thrusts.
/// </summary>
/// <param name="ship"></param>
/// <returns></returns>
private Vector2D CalculateInstantAcceleration(Ship ship)
{
Vector2D totalAcc = new Vector2D(0, 0);
// add gravity from each star
foreach (Star star in theStars.Values)
{
totalAcc += CalculateForce(ship, star);
}
// if thrust add enginestrength
if (ship.IsThrusting())
{
totalAcc += (ship.GetOrientation() * engineStrength);
}
// return accumulated vector
return(totalAcc);
}
